Questions tagged [surfactants]
Questions about compounds that lower the surface tension (or interfacial tension) between two liquids or between a liquid and a solid.
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Is there such a thing as a "minimal soap" molecule?
Wikipedia's Soap gives sodium stearate as an example of soap, and apparently I've been eating it:
Sodium stearate is the sodium salt of stearic acid. This white solid is the most common soap. It is ...
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What is the difference between hand wash and body wash soap?
I do not like body wash always with strong favor. I like hand wash soap to wash my body. Are they difference at all?
Thanks for the comments, so that I add the following information
I am really sorry ...
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What is the opposite of a surfactant?
Surfactants decrease surface tension between two fluids. What do you call a substance that increases the surface tension between two fluids? How is this effect acheived?
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Soap and rain water, why does it not rinse off?
I am in Papua New Guinea at the moment, where rain water harvesting is the most common way of getting water.
When washing hands, the soap feels hard to rinse off, and my skin feels "greasy".
I read ...
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Why does shampoo lather much more the second time it is applied?
When I shampoo my dirty hair, the first time it does not lather very much. The second time it lathers a lot. Why is this?
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What are "tensides"?
I was reading about chemicals that control pore size of polyurethane foams and there it was mentioned that "tensides" decrease pore size. What are tensides? I assume it's the opposite of a surfactant, ...
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Is it known for sure that bases feel slippery because of the production of soap/surfactant?
Discussion around the question Why does bleach feel slippery? has started me thinking about the saponification explanation for the slippery feeling of basic solutions.
According to Wikipedia:
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What is the purpose of froth in washing clothes?
I stay at a rented place and there is no washing machine. I, now, wash clothes in a bucket. When I add detergent, sometimes there is froth, sometimes there is not. I wonder if this had any impact on ...
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How do I lower the surface tension of water without using a detergent?
For many years I've used a Rainbow vacuum, which uses a reservoir of water as the filter. While I'm quite pleased with it, I've found that when trying to vacuum cement dust or wood ash not all of ...
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What turns clear liquid soap blue? [closed]
Liquid soap that sits in metal pump handles turns blue after a week or so, as in this photo comparing the soap in its initial clear state and then after pumping from the dispenser.
The pumps are ...
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What's the chemical nature of a dishwasher's rinsing agent?
It seems that a rinsing agent helps the dishes in the dishwasher dry much better than they do without it (which I recently noted on my new dishwasher). What molecules are used in the composition of ...
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Why does Dead Sea water feel greasy?
The best explanation I found so far is this:
These salts (magnesium, potassium, sodium, etc.) are responsible for the "greasy" feel of the water.
But it doesn’t say which salts exactly are ...
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Stripeless cleaning of windows
Last week I was discussing with a friend how we thought the stripeless cleaning of windows is achieved when using a cleaner like Windex Glass Cleaner as opposed to just using hot water, in which case ...
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Quantifying soapiness; there's pH, pKa and pO2, is there a p_soap or p_surfactance?
Yes, $\mathrm{pH}$ is a concentration, $\mathrm{p}K_\mathrm{a}$ is a dissociation constant, and $\mathrm{pO_2}$ is a partial pressure. These are (roughly speaking) ways to indicate how much of a key ...
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The sponge isn't foaming up, why?
When I add dish soap to a sponge it is able to foam up. But if I leave the sponge alone for an hour, it doesn't foam up, not even if it is wetted.
Why? The sponge should still contain dish soap an ...
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Does borax do anything more for "boosting" detergent than adding active oxygen would?
Borax, $\ce{Na2B4O7}$, is often marketed as a "laundry booster" under the brand "20 Mule Team Borax". The unit crystal of borax can be seen below.
Other laundry products in the past have added ...
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The entropy change during micellization
I was reviewing the thermodynamics of micelle formation from the Wikipedia page and this book. I understood most of the arguments but micellization is supposed to be an entropy driven process with a ...
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What exactly happens while washing clothes
I am reading about soaps , micelles and all that. I understand how soap behaves in water contaminated by oil. Soap helps in emulsifying the oil into water.
Let us suppose now we have dirt(i.e oil, ...
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Removing wine stains from a decanter
I have a decanter which I use fairly often to pour out wines. I typically rinse it with hot water after the last wine has come out, but I cannot prevent it from forming 'residual' wine stains over ...
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Is there a type of detergent/surfactant that evaporates at STP?
Are there any type of detergent/surfactant chemicals that would be good for removing dirt and grease from fabric that also would evaporate from the clothes within, say, 24 hours leaving no residue?
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Why do surfactants lower the surface tension
Everybody knows that detergents, or generally amphiphilic substances, lower the surface tension. Of water, usually.
I wonder if that's true for any polar solvent (most likely), i.e. will the same ...
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Lemon juice, the ultimate anti-foaming agent?
As an amateur soda maker, I have noticed an odd phenomenon: lemon juice sodas do not foam. Virtually every juice I have tried foams to some degree when mixed with carbonated water. Lemon juice does ...
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Dyes that can stain oil and water
Is there such a thing as a dye that can stain both oil and water? In other words, does anyone know of an amphiphilic dye? Maybe a surfactant that is also a pretty shade of blue? Or maybe turn one ...
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What is the substance in the new water cooler filter that give bubbles and taste a bit like soap
Recently the water cooler was replace with a new filter.
However, when I refill my water kettle with the water from the water cooler, there are many bubbles and the taste was a bit like soap.
What ...
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Thermodynamics of micellisation
Micellisation is found to be spontaneous i.e. $\Delta G < 0.$ It's found that $\Delta S > 0,$ which was intuitive since, solvated molecules are released. And, it may be most loosely started that ...
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Do surfactants exist in a gas phase?
I am wondering if there are surfactants that exist in a gas state that can be used to reduce the surface tension of a liquid.
I know its a broad question, so for example, are there any gases that ...
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Biodegrability of straight chain and branched chain detergents
From NCERT Chemistry: Textbook for class XII, Part II [1, p. 461]:
Main problem that appears in the use of detergents is that if their hydrocarbon chain is highly branched, then bacteria cannot ...
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Can cationic species form micelles?
Most of the books dive into formation of micelles by soaps. They go on talking about alkyl sulphate and carboxylates, but never do they mention anything about cations. My textbook says that at ...
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Surface Chemistry - Dipole Moment of Surfactant with Water and Phases of a Monomolecular Layer
Recently, I have been trying to study surface chemistry and I have come across questions that I do not understand how to answer. I understand what a dipole moment is, defined as a charge separation ...
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How can I make an alloy wetter?
I'm trying to make a Bismuth-Indium based low-melt alloy wetter (specifically, better at wetting to solid metals and glass). I've tried adding gallium, which obviously works, but due to its metal-...
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What is the highest known temperature where micelles exist?
What are the two liquid phases involved in the formation of roughly spherical micelles at highest possible temperatures? What about a surfactant? At how high temperatures have micelles been observed ...
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Why does copper sulphate (CuSO4) in water increase surface tension?
So, recently for school, I did an experiment on surface-tension. We tested Water, Salt, Sugar, Dissolvable Panadol, Coffee Powder, Vinegar, Detergent, Flour, Methylated Spirits, Oil & Detergent, ...
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Why does soap reduce surface tension of water
One explanation I read is that soap's long non-polar end will seek the air at the interface between water and air, and that the ionic end will form ionic-dipole bonds with the water. In the process of ...
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Reaction of soap with water
I've seen it many times... Why does soap become foam-like when it reacts with water (moisture) or when we touch it with wet hands.. What compound actually causes this physical change? And why does ...
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Is it possible to store a Tween 80 stock solution?
I am making a stock solution of Tween 80 (0.05 % w/v) and each experiment requires just 15 ml of the stock solution. Is it possible to make a large batch (about 100 ml) and store it somewhere? If so, ...
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What non-poisonous chemicals can get rid of SLS effectively?
Whenever I brush teeth, there are some kind of bubbles sticking inside the cavity and that's uncomfortable, it should be SLS as found on the internet. Does anyone know how do I get rid of those ...
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How does NaCl (or any inorganic salt) increase surface tension?
Does the compound "prefer" to stay in the solution?
If yes, wouldn't the surface tension of the solution be equal to that of pure water, since only water is in the surface?
See: Does NaCl reduce the ...
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Why isn't washing up liquid dry
Washing up liquid is wet and it is added to water. Why does it not come in a half size package and you add the water yourself? In the same way washing powder is?
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What is the difference between the roles of a surfactant and a stabilizer in the process of nanocrystal growth?
The crystals that I am synthesizing use two different stabilizers CTAB and SDS, but they say one is used as a surfactant and since they are both stabilizers what is the need for both?
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How do surfactants spread in the case of multiple materials?
For example, consider a pot of water with a drop of oil floating on it, with surfactants present in the water.
Will the surfactants in the water spread evenly across all three interfaces (water/metal,...
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How can surface excess be negative?
If we have interphase of two phases $\alpha$ (water) and $\beta$ (air), surface excess is defined as
$$\Gamma_i = \frac{n_{i,\mathrm{tot}} - n_{i,\alpha} - n_{i,\beta}} A = \frac{n_{i,\mathrm{int}}} A,...
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Anti-foaming agent for HCl + copper chloride solution
I am trying to etch my own circuit boards at home, and have whipped up some DIY cupric chloride etchant (just CuCl with a bunch of free HCl)
The problem I have found is that when I try to bubble air ...
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How do lyophilic colloids reduce surface tension?
It's given in my textbook that the surface tension of lyophilic/hydrophilic solutions is lower than water.
But my intuition says, since in lyophilic solutions the interaction between a lyophilic ...
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How can I solubilize fragrance oil into polyvinyl acetate/clear glue?
I'm a high school student who makes slime for fun, using polyvinyl acetate (PVA) glue and borax as my main ingredients.
Earlier, I had the idea of adding fragrance oils to clear glue. However, because ...
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Why are critical micelle concentrations so large?
Dissolving a non-polar molecule in water incurs a free energy cost of about $10 kJ/(mol \cdot nm^2)$ (source: http://bionumbers.hms.harvard.edu/bionumber.aspx?&id=101826)
The entropy gained from ...
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Suppressing flammable foam formation in electrolysis
I often use electrolysis to remove rust and other junk off of steel parts. My general setup is:
Electrolyte: Sodium bicarbonate + distilled water.
Anode: Plain carbon steel
Cathode: Carbon steel, ...
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What are the differences between the various household surfactants?
In a typical household, the following surfactants are found, among others:
Soap / handwash
Shower gel
Shampoo
Dishwashing agent
Washing powder / liquid
From my understanding, the role of all these ...
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Does using stonger soaps help me lose weight?
Soaps are amphiphilic molecules that, practically, removes body oils from the surface of the skin. The body, on the other hand, always replenishes sebum through the sebaceous glands after a certain ...
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Difference between Soap and Detergent
In most articles and texts that I've read, soaps and detergents seem to be talked about collectively. I know that they are both surfactants and that soaps are usually natural, in comparison to ...
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Impact of detergent on internal living tissue?
There was some spirited debate between the members of my chemistry lab today about the theoretical consequences of ingesting a large amount of the detergent Triton X-100 at a 100% concentration. The ...
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